And then after the progression we finally come to a 10th fret G (using an open A shape but barred using two fingers to make the whole shape), they pause for a moment with Weir doing a note-noodle off of the 10th fret D chord surrounding notes (open E shape) while Garcia sets it up using a tried and true Sugar Magnolia hook (think Come on, honey, come along with me), then they all hit a D chord, and instantly the band has switched keys from the key of D to the key of G, and they're ready for IKYR.